IMPACTS OF CLIMATE CHANGE ON CROPPING SYSTEM AND ITS IMPLICATION FOR AGRICULTURE IN CHINA

Based on the analyses on amplitudes of historical variation of temperature and precipitation in the past 500 years and latest 100 years,according to the regional climate change scenarios for China estimated by composite GCM,the potential impacts of climate change on cropping systems in China in future are simulated and assessed using the cropping system model development specially for the Chinese cropping patterns.It is shown that under the projected future climate change by 2050 the most parts of the present double cropping area would be replaced by the different triple cropping patterns while the current double cropping area would shift towards the central part of the present single cropping area.More explicitly,the northern boundary of triple cropping area would shift from its current border at the Changjing River to the Huanghe River,a shift of more than 5 degrees of latitude.And the shift of multiple cropping areas leads to a significant decrease of single cropping area.Furthermore,considering the changes mentioned above in combination with the likely negative balance of precipitation and evapotranspiration and,therefore,increase of moisture stress(i.e.less water availability),as well as the possible increase of heat stress disaster and decrease of LGS(length of growing season),the potential implication of climate change for agriculture in China are also analyzed roughly in this paper.As a result,however,it is still very difficult to reach a specific conclusion that the future climate change will he favorable or unfavorable to farm in China because of the complicated Chinese farming patterns,the complex-various social and economic environment of agricultural development and,especially,a great scientific uncertainties in the investigation/prediction of climate change.